I'd like to think that this argument is trotted out due to the feeble performances of Bernard Foley over the past 3-9 matches.
The signs were there in the Wales game that he was out of form. However he kicked straight from between the two 15m lines and the 40 so everyone was happy to overlook it..
Then there was France.
Then there was Ireland.
And Regarding "non-waratahs players being left out of the side".
Kyle Godwin.
Matt Hodgeson.
Hodgson is unlucky not to be there but we rarely pick two 7s and regardless of how much you dislike Hooper, he's unlikely to lose his spot.
Godwin is unlucky in that To'omua and Leali'ifano are fighting it out for the 12 jersey which wasn't settled at the start of the tour and Godwin only plays 12 (particularly for his eventual test debut). He's unlikely to get a bench spot just as a 12 and no coach is likely to just give him a cap because he's on tour when they consider him the third best option in that position.